Style consistency: don't end error messages with exclamation points.

lib/codegen/meta/cdsl/isa.py

@@ -54,7 +54,7 @@ class TargetISA(object):
         self._predicates = dict()  # type: Dict[PredKey, PredNode]
 
         assert InstructionGroup._current is None,\
-            "InstructionGroup {} is still open!"\
+            "InstructionGroup {} is still open"\
             .format(InstructionGroup._current.name)
 
     def __str__(self):

lib/codegen/meta/cdsl/typevar.py

@@ -231,7 +231,7 @@ class TypeSet(object):
     def __hash__(self):
         # type: () -> int
         h = hash(self.typeset_key())
-        assert h == getattr(self, 'prev_hash', h), "TypeSet changed!"
+        assert h == getattr(self, 'prev_hash', h), "TypeSet changed"
         self.prev_hash = h
         return h
 

lib/codegen/src/verifier/mod.rs

@@ -207,7 +207,7 @@ impl<'a> Verifier<'a> {
             );
         }
         if is_last_inst && !is_terminator {
-            return err!(ebb, "block does not end in a terminator instruction!");
+            return err!(ebb, "block does not end in a terminator instruction");
         }
 
         // Instructions belong to the correct ebb.
@@ -1163,7 +1163,7 @@ mod tests {
     macro_rules! assert_err_with_msg {
         ($e:expr, $msg:expr) => {
             match $e {
-                Ok(_) => panic!("Expected an error!"),
+                Ok(_) => panic!("Expected an error"),
                 Err(Error { message, .. }) => {
                     if !message.contains($msg) {
                         panic!(format!(